package com.burns.rbac.config;

import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.plugin.*;
import org.apache.ibatis.reflection.DefaultReflectorFactory;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.SystemMetaObject;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.type.TypeHandlerRegistry;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.sql.Connection;
import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import java.util.regex.Matcher;

/**
 * 拦截StatementHandler类中参数类型为Statement的 prepare 方法
 * 即拦截 Statement prepare(Connection var1, Integer var2) 方法

 */

@Component
@Slf4j
@Intercepts({@Signature(type = StatementHandler.class, method = "prepare", args = {Connection.class, Integer.class})})
public class MybatisSqlLoggerInterceptor implements Interceptor {


	@Override
	public Object intercept(Invocation invocation) throws Throwable {

		StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
		//通过MetaObject优雅访问对象的属性，这里是访问statementHandler的属性;：MetaObject是Mybatis提供的一个用于方便、
		//优雅访问对象属性的对象，通过它可以简化代码、不需要try/catch各种reflect异常，同时它支持对JavaBean、Collection、Map三种类型对象的操作。
		MetaObject metaObject = MetaObject
				.forObject(statementHandler, SystemMetaObject.DEFAULT_OBJECT_FACTORY, SystemMetaObject.DEFAULT_OBJECT_WRAPPER_FACTORY,
						new DefaultReflectorFactory());
		//先拦截到RoutingStatementHandler，里面有个StatementHandler类型的delegate变量，其实现类是BaseStatementHandler，然后就到BaseStatementHandler的成员变量mappedStatement
		MappedStatement mappedStatement = (MappedStatement) metaObject.getValue("delegate.mappedStatement");
		//id为执行的mapper方法的全路径名，如com.uv.dao.UserMapper.insertUser
		String id = mappedStatement.getId();
		log.info("id ==> " + id);
		//sql语句类型 select、delete、insert、update
		String sqlCommandType = mappedStatement.getSqlCommandType().toString();
		log.info("类型 ==> " + sqlCommandType);

		BoundSql boundSql = statementHandler.getBoundSql();
      
		// 获取节点的配置
		Configuration configuration = mappedStatement.getConfiguration();
		// 获取到最终的sql语句
		String newsql = getSql(configuration, boundSql, id);
		log.info("拦截的sql ==>: " + newsql);
		long start = System.currentTimeMillis();
		Object returnValue = invocation.proceed();
		long end = System.currentTimeMillis();
		long time = (end - start);
		log.info("sql耗时 ==>: " + String.valueOf(time));
		return returnValue;
		//return null;
	}

	@Override
	public Object plugin(Object target) {
		return Plugin.wrap(target, this);
	}

	@Override
	public void setProperties(Properties properties) {
	}


	/**
	 * 封装了一下sql语句，
	 * 使得结果返回完整xml路径下的sql语句节点id + sql语句
	 *
	 * @param configuration
	 * @param boundSql
	 * @param sqlId
	 * @return
	 */
	private String getSql(Configuration configuration, BoundSql boundSql, String sqlId) {
		String sql = showSql(configuration, boundSql);
		StringBuilder str = new StringBuilder(100);
		str.append(sqlId);
		str.append(":");
		str.append(sql);
		return str.toString();
	}

	/**
	 * 如果参数是String，则添加单引号， 如果是日期，则转换为时间格式器并加单引号；
	 * 对参数是null和不是null的情况作了处理<br>
	 *
	 * @param obj
	 * @return
	 */
	private String getParameterValue(Object obj) {
		String value = null;
		if (obj instanceof String) {
			value = "'" + obj.toString() + "'";
		} else if (obj instanceof Date) {
			DateFormat formatter = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.CHINA);
			value = "'" + formatter.format(new Date()) + "'";
		} else {
			if (obj != null) {
				value = obj.toString();
			} else {
				value = "";
			}

		}
		return value;
	}

	/**
	 * 进行？的替换
	 * @param configuration
	 * @param boundSql
	 * @return
	 */
	public String showSql(Configuration configuration, BoundSql boundSql) {
		// 获取参数
		Object parameterObject = boundSql.getParameterObject();
		List<ParameterMapping> parameterMappings = boundSql
				.getParameterMappings();
		// sql语句中多个空格都用一个空格代替
		String sql = boundSql.getSql().replaceAll("[\\s]+", " ");
		if (!CollectionUtils.isEmpty(parameterMappings) && parameterObject != null) {
			// 获取类型处理器注册器，类型处理器的功能是进行java类型和数据库类型的转换　　　　　　　
			// 如果根据parameterObject.getClass(）可以找到对应的类型，则替换
			TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry();
			if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) {
				sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(parameterObject)));

			} else {
				//MetaObject主要是封装了originalObject对象，
				// 提供了get和set的方法用于获取和设置originalObject的属性值,
				// 主要支持对JavaBean、Collection、Map三种类型对象的操作
				MetaObject metaObject = configuration.newMetaObject(parameterObject);
				for (ParameterMapping parameterMapping : parameterMappings) {
					String propertyName = parameterMapping.getProperty();
					if (metaObject.hasGetter(propertyName)) {
						Object obj = metaObject.getValue(propertyName);
						sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
					} else if (boundSql.hasAdditionalParameter(propertyName)) {
						// 该分支是动态sql
						Object obj = boundSql.getAdditionalParameter(propertyName);
						sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));

					} else {
						//打印出缺失，提醒该参数缺失并防止错位
						sql = sql.replaceFirst("\\?", "缺失");
					}
				}
			}
		}
		return sql;
	}

}
